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Alsa: Keep 8 samples in input buffer to avoid reading corrupted samples

This commit is contained in:
Andreas Eversberg 2016-08-13 15:19:12 +02:00
parent 541eafe59e
commit 7d111546c4
1 changed files with 7 additions and 5 deletions
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12
src/common/sound_alsa.c
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@ -218,6 +218,8 @@ int sound_write(void *inst, int16_t *samples_left, int16_t *samples_right, int n
return rc;
}
#define KEEP_FRAMES 8 /* minimum frames not to read, due to bug in ALSA */
int sound_read(void *inst, int16_t *samples_left, int16_t *samples_right, int num)
{
sound_t *sound = (sound_t *)inst;
@ -227,12 +229,12 @@ int sound_read(void *inst, int16_t *samples_left, int16_t *samples_right, int nu
/* get samples in rx buffer */
in = snd_pcm_avail(sound->chandle);
/* if less than 2 frames available, try next time */
if (in < 2)
/* if not more than KEEP_FRAMES frames available, try next time */
if (in <= KEEP_FRAMES)
return 0;
/* read one frame less than in buffer, because snd_pcm_readi() seems
* to corrupt last frame */
in--;
/* read some frames less than in buffer, because snd_pcm_readi() seems
* to corrupt last frames */
in -= KEEP_FRAMES;
if (in > num)
in = num;